The Ducati team has confirmed Casey Stoner will return to racing action as scheduled at this weekend's Portuguese Grand Prix.

Stoner has skipped the last three races of the season as he recovered from the mysterious illness that affected him earlier this year.

During his time away from the track, the Australian has been under constant supervision of a medical team, undergoing a series of exams and special tests.

Ducati said the results of the tests had excluded pathological anomalies of cardiovascular, respiratory or neurological origins. The exams and inspections also failed to show up any kind of virus or infection.

However, the medical report revealed low blood pressure levels and a lack of sodium, two factors that doctors believe were the main cause of the physical problems Stoner suffered earlier in the season.

According to the team, the doctors said it was absolutely necessary that Stoner rested in order to avoid aggravating his physical debilitation.

Stoner underwent a final medical exam before leaving Australia and doctors confirmed he is in better physical shape, although still not fully recovered.

The 2007 world champion will be back in action at Estoril this weekend, and will remain under medical supervision, with a new sodium-rich diet aimed at raising his blood pressure and muscular functionality.

"I'm definitely looking forward to the race weekend," said Stoner. "Having three races off is the biggest period away from racing in my life. It was very difficult to accept the advice of the doctors to stop racing.

"In the past I have raced even when injured, like in the last few races of the 2008 season when my wrist was broken, but this time it was really not possible and of course I felt very sorry for the team.

"Now I'm looking forward to getting back together with the team and everyone and I hope I'll be able to be more competitive than I was in the past, but we will have to wait and see.

"The doctors have put me on some salt tablets to increase my sodium levels but we will have to see if it helps. We will understand more during the weekend.

"Of course it's going to be difficult: at first we won't know if it will work because I've been off the bike so long that in any case my muscles will take some time to get race fit again. But, as I said, I'm looking forward to getting back and to starting work on the bike, looking towards the future."

Team boss Livio Suppo added: "We are really pleased that Casey is back with us. We never had any doubt that he would be with us once again at Estoril. We know that he is still not in 100% peak fitness and we just hope that over the last four races of the season he can gradually build his strength and work with Nicky to help Filippo develop the bike.

"With that goal in mind we have a few new things to try this weekend, in particular a new fairing which is designed to make the bike handle better in strong winds and fast direction changes. I really hope Nicky's luck turns around after Misano because his season has got gradually better and I'm sure he'll keep that trend going this weekend."

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